Filter



-in the filtration of certai `filter medium or cloth uponI the' surface'the including filter medium andfsupportin Y therefor, which can bereadilyfclia'ngd,`

manner of dividing the into lter sections. f

One of the prime objects V"offth" to provide a drainage deckgor'ii l y Hv porting surface for rotary: vaciiuf` vfilters"ii'fhich will be strongand rugged a'ndfea'sily,l `andreadily positioned on the drum ormovedJthi-*efrom Whilev at the same time vvi be' fcapableoit' expandingor contracting und treni "ciangres in temperature conditionswitho'utmatr fecting, the filter assembly'oi placing hvan upon the componentparts ther of Such ture and arrangement is stance, the de-waxing of o isections of the drum mayfb svulpj4 e`d o tmperatures varying asmuch'z'as`lrfrom -{2D 1?. to 212 F. in a single revolution .of the `di"ur`n. I Y Another object of the inv njtio'n isitofproyide a simple andeffective meansfof,attacnmgfth drum and to hold the sani'esecurely'butdY ach.-

ably thereon.

A further object of the ifvention is to a novel arrangement in the lterdeck ay i shed. [j or repaired in a quick and simplemannerwithj" 'outthe necessity of any solderingbi welfding,

which operations are undes'iralol'e, if`not ijrnpos# I sible when thelter Vis operatingwitn substances n o of a volatile or inflammabIenaturell 1, Theiiererelshoulders n of eeendivision strip With these andother Objectsn View". the nprovideshelves orsuppoiting surfaces uponwhich vention consists in the constructiony and novel safest"th'elngigudial edge portions 0f` a fllter combination and arrangement cf'parts herein'- Q 'vrediumfsupportigelement in thefOI-m ofrelaafterfully described, illustrated inthe aeeomtivelye rigid-mete is,one oiwhioh extends the Danyng drawing. and parti- Culal'ly Pointd outlengtlii-ofthe filter] dr'llrrrbetween each division in the appendedclaims, it being understeod'tha l strip supported et itsopposiielongitudinal sides variouschanges may be madefnthe Szepri- 4.5-I onineshoulders llias'jus't described. The lter portion and minor detailsfofM.the construction clothsupprtigmemberror plate `AI8 is provided withinthescope of the claims without depart- 'with {nuifnerous p'rforationsi9, substantially ing from the spirit `of theinventio'n or sacricj'thrflughugns a1-gamin" @der that the uquid or ine any 0f the advantagesth'ereof. iil'tr'latek clriiiwnv through the filter medium may In thedrawing: y lf .i 450` pass ltnrougli'theseperioratlons VI9 andultimately Figure 1 iS 2f fragmentaryC TQSSvSeCtiQnal viewthroughfthefdrainage pipes. fl. 1 vIn the preferred of a. lter drumembodyingithe features ofithe constructiomtheplate I8 is also providedwith a present invention, the view-being taken in a plane series ofaligned` openings. "extending longisubstant'ially at a right anglewiththeaxis of tudinallyand substantiallycentrally of the plate. the drum; f.i i 65These openings Aareadapted to accommodate apmeans.

propriete elements or means for securely holding the plate I8 inposition on the drum with its longitudinal edges resting on theshoulders I1 of the division strips, as will hereinafter more fullyappear.

It is generally desirable to provide an intermediate filterclothsupporting` medium above the surface of the platey I8. To this end,a relatively coarse mesh wire cloth 2| is positioned on the uppersurface of the plate I 8, with its edges folded over and under thelongitudinal edges of the plate, as indicated at 22, to rest upon thelateral shoulders I1 of the division str ips. Thus, the innot be sprungor forced downwardlyA a distance any greater than the height of theshoulders I1. This assures the maintenance of a predetermined minimumdrainage space between the surface of the drum I and the supportingplate I8.

As is well known, the lter medium 3|, which ris generally a woven brousmaterial or cloth, is

bers in a continuous and uninterrupted sheet, the

Y, two opposite edges ofwhich are shown and retermediate supportingmedium 2-,I is'.l securely and firmly held stretched in placel` on' theupper sur-.-`

face of the plate I8, but in a quickly and readily detachable manner. Ateach. of theialigned central openings 2 0 of the plate' |8`, theintermediate `A supporting material 2| lis also provide'd'f-with a'registering opening, the edges .thereof being i foldedo'ver'and undertheedges'of the plate opening 20,' as indicated at 23|. i

' In the preferred arrangement the filter drum I0 is provided with aplurality of aligned permanently attached studs 24 so arranged as toregister with and extend into eachrofthe plate openings j v2|),the studs24 preferably being screw-threaded, shown. A bushing or washer 25 isadapted to b e' loosely receivedfon each stud 24, and 'this fbushing4 25preferably takes the form substan- `tially'lcf'av cup, having an opening26 in itsbotvtomfofl a'diameter relatively large as compared y fwiththatof thefstud 24, in order that the cupj like bushing may t over thestud in a relatively f floosefashion.` Th'e'upstandlng side wall of 'thej, bushing 25 provided with an annular outwardly extending shoulder 21,the under surface of 'which is preferably beveled to cooperate withofthe openingf through the plate I8. A'lock nut or other suitablescrew-threaded element 2 9 isy adapted to be screwed down onto thescrewthreaded endof the stud 24, and force the bushing` downwardlythereon, until the beveled shoulders 21 contact with and bear againstthe intermediate filter cloth supporting medium,

where the same is foldedfover the beveled edges amount of movement ofthe plate I8 and bushing 25 inany lateral direction as a consequence ofexpansion or contraction in the plate I8 and wire cloth 2|, incident tosharp and wide changes in temperature. Preferably, a sheet metal shieldor sealing. member 30, in the form of an inverted cup and having arelatively tight flt within the interior of the bushing 25, is slippedthereinto to cover the nut 28 and present a smooth plane'surfacethereover, and at the top of the bushing 25 so that the filter cloth 3|may have a smooth surface presented to it over the plate hold-down Inorder to limit the downward movement o f Vthe plate I8, there extendslongitudinally along the surface of the drum I Il and in line with thestuds 24, a series of interrupted `ridges 32 which rise ltoapproximately the same height above the surface of the drum IU as do theshoulders Il of the division strips. Thus, upon being .forced downwardlyand secured in position by the central attaching and holding means, theplates I8 are limited centrally so that they will ceived within thegroove I6, provided in the division ystrip '.I4, thevgroove in thisparticular division strippreferably being somewhat deeper than thesimilar groove i'n the other division the'two'loose ends of the filtercloth. In the a"correspondingly beveled surface 28 at the edge preferredarrangement, one end 32 of the cloth is positioned in the groove' 6 to tsnugly against the bottom and both side-walls thereof, and a wedgeyorcalking member 33 of wood, lead, or other appropriate substance, isforced into the groove in order to ltightly wedge the loose en d 32ltherein. The opposite loose end 34 of the filter cloth is then insertedinto the groove and securely wedged therein by means of a wedge orcalking element 35 similar to the wedge 33. If desired, spacing rod 38may overlie the calking 35 to securely hold the same againstdisplacement ated that any slack in the filter cloth can be taken up andthe same caused to be stretched tightly y around the drum by forcing asuitable amount or extent of the cloth into the respective grooves I6.After the ltercloth is thus stretched around the drum on the supportingsurfaces I8 and 2| and securedin'place by the wedging just described,the usual wire winding 28 may be placed around the drum` over theoutside surface of the filter cloth in a manner well known in the art.

From the foregoing description, it will be appreciated that the variousparts of the filter drainage` deck of the present invention may bequickly and readily assembled upon the drum, removed therefrom, andsubstitutions made, or repaired with the utmost ease and dispatch. Itwill be further appreciated that soldering or the use of heat,undesirable when the filter is being used with materials of acombustible nature, are entirely dispensed with and the various changes,such as replacement of lter cloth, may be accomplished by the use of afew mechanical manipulations.

Sincev one of the prime purposes of the invention is to provide adrainage deck which may freely expand and contract under the influenceof rapid and wide temperature fluctuations without imposing serious anddisruptive strains upon other parts of the lter drum, the plate memberelated that the plate I8 and the intermediate filter cloth supportingmaterial 2l may readily expand in either or both directions as well asto contract correspondingly without imposing any substantial stress orstrain upon the various elements constituting and associated with thedrainage deck.

While the central hold-down assembly, comprising the studs 24,cup-shaped bushings 25, and lock nuts 29, have been found to bedesirable in the construction of the present invention, it is to beunderstood that the broader features of the present novel drainage deckand arrangement are not limited to this specific hold-down means, butsuch means may take any desired form that will serve the purpose ofsecuring the plate I8 in place upon the shoulders I1 and permit adesired amount of lateral movement thereof incident to expansion andcontraction under the influence of temperature changes. It is alsounderstood that other or additional intermediate filter cloth supportingelements may be utilized in a manner known to those skilled in the art.

What is claimed is:

l. In a drum type lter, a filter section comprising a pair. of divisionstrips extending longitudinally of the drum and having lateralshoulders, a relatively rigid perforate plate supported at itsopposite'longitudinal sides upon said shoulders, means between the edgesof said Vplate for holding the same in position against displacemeansfor securing said cloth in position over the surface of said plate.

' 2. In a. drum type filter, a-i'ilter section comprising a pair ofdivision strips extending longitudinally of the drum and having lateralshoulders, a relatively rigid perforate platesupported at its oppositelongitudinal sides upon said shoulders, adjustable means between theedges of said plate for detachably holding the same in posisame inposition against Vertical displacement ment, filter cloth extending oversaid plate, and

tion against displacement, lter cloth extending 1 division strips andcooperating with said plate for holding the same in position againstdisplacement, lter cloth extending over said plate, and means forsecuring said cloth in position over the surface of said plate.

4. In a drum type filter, a filter section comprising a pair of divisionstrips extending longitudinally of the drum and having lateralshoulders,a relatively rigid perforate plate supported at its oppositelongitudinal sides upon said shoulders, the width of said plate beingless than the distance between the far edges of adjacent shoulders,means between the edges of said plate for holding the same in positionagainst vertical displacement but allowing limited lateral movementthereof, lter cloth extending over said plate, and means for securingsaid cloth in position over the surface of said plate.

5. In a drur type lter, a filter section comprising a pair of divisionstrips extending longitudinally of the drum and having lateralshoulders, a relatively rigid perforate plate of a width less than thedistance between the far edges of adjacent shoulders and supported atits opposite longitudinal sides upon said shoulders in a manner forlimited lateral movement thereon, means between the edges of said platefor holding the but allowing limited lateral movement thereof, filtercloth extending over said plate, and means for securing said cloth inposition over the surface of said plate.

6. In a drum type filter, a filter section comprising a pair of divisionstrips extending longitudinally of the drum and having longitudinalgrooves and lateral shoulders, a relatively rigid perforate platesupported at its opposite longitudinal side upon said shoulders, meansbetween the edgesof said plate for holding the same in position againstdisplacement, lter cloth extending over said plate and into the groovesof the respective division strips, and means for securing said clothwithin said grooves.

7. In a drum type filter, a lter section com prising a pair of divisionstrips extending longi tudinally of the drum and having lateralshoulders, a relatively rigid perfor-ate plate supported at its oppositelongitudinal sides upon said shoulders, said plate having a series ofopenings between its longitudinal edges, screw-threaded studs carried bysaid drum and extending into said openings, means associated with saidstuds for forcing said plate downwardly and holding the same againstvertical displacement, means for limiting downward movement of saidplate, filter cloth extending over said plate, and means for securingsaid cloth in position over the surface of said plate. v

ROBERT GEORGE ALBERT WEISS;

